Brook



(No Model.)

A. E. HOLBROOK 82; J. F. HARDING.

AIR DOOR FOR COAL MINES.

No. 597,147. Patergted Jan. 11, 1898.

UNITED STATES PATENT rricE.

ALBERT EDW'IN HOLBROOK AND JOHN FRANCIS HARDING, OF ABERTILLERY,ENGLAND.

AlR-DOOR FOR COAL-MINES.

SPECIFIGATION forming part of Letters Patent No. 597,147, dated January11, 1898.

Application filed June 30, 1897. Serial No. 642,974, (No model.)

' JOHN FRANCIS HARDING, residing at 33 Castle Street, Abertillery, inthe county of Monmouth, England, subjects of the Queen of Great Britain,have invented certain new and useful Improvements Relating to Air-Doorsfor Goal-Mines and Underground Torkin gs, of which the following is aspecification.

This invention consists of improvements relating to air-doors forcoal-mines and underground worlzin gs, our object being to providesimple and reliable means for effecting the automatic opening andclosing of such doors by the movement of a passing wagon or vehicle.

v In the accompanying sheet of explanatory drawings, to be hereinafterreferred to, Figure 1 is a front elevation of a pair of air-doorsarranged in combination with our opening and closing appliances. Fig. 2is a sectional plan through the line a Z), Fig. 1, the fixed framing ofthe doors being represented by dotted lines. Fig. 3 is an end elevationshowing the connection between the doors and the operating mechanism.Fig. at is a plan showing the endless-cord connection between the pairof doors. Fig. 5 is a front elevation representing a modifiedarrangement of the operating mechanism.

The same reference-letters in the different views indicate the sameparts.

In carrying our invention into effect we employ a weight, such as A, forthe purpose of keeping the doors B B in their closed position, theweight-suspension cord or chain 0 being connected with one door only,but as the two doors are connected by the endless cord or chain D therising or falling movement of the weight A will produce a movement ofthe doors B B in opposite directions, either toward or away from eachother. The door B is connected with the upper end of the lever E, and onthe outer ends of the axis or pivot-pin of such lever E we mount theshorter arms or levers F F, which are in turn connected with the leversG G. Each length of rail H H, adjacent to the door B, is arranged inlateral guides J, and its end remote from the door is attached to itssleeper or bearer by a stud K, Fig. 3, the body of the stud fittingloosely within a hole formed for its reception in the rail. The rails HH are also connected by a short pitman or rod L L with the levers G G,and the whole of the levers and connections are so arranged that whenthe doors are closed the rails H H are held in the tilted or inclinedposition illustrated at Fig. 3; but on the approach of a wagon orvehicle on the rails toward either side of the doors the tilted railswill be automatically depressed by the load imposed upon them by thevehicle-wheels, such load being sufficient to raise the counterweight Aand to open the doors by means of the connecting-levers E F F G G andshort pitman or rods L L. When the wagon or vehicle has passed throughthe doorway and its wheels are clear of the movable rails, the doorswill be closed by the descent of the weight A and the rails again raisedto their inclined or tilted position.

The doors are hung by the runners or pulleys M upon the supporting-barN, fixed to the casing, and they can thus be moved readily under theaction of the counterweight A or the force imposed by the passing wagonor vehicle, as described.

Either rail of the pair adjacent to the doors can be made the movablerail and connected with the door-operating mechanism.

The illustration at Fig. 5 represents the rail remote from the lever Earranged as the movable rail. The rail adjacent to the lever is fixedand forms no part of the door-operating mechanism.

Having now described our invention, what we claim as new, and desire tosecure by Letters Patent, is-

In combination with the sliding doors, the endless cord connecting themto move in unison in opening and closing, the weight for closing thedoors automatically, the lever E connected directly to one gate, therock-shaft F adjacent to the track and carrying the lever, the movabletrack-section adjacent to the gate and the arm under said sectionconnected to the rockshaft.

In witness whereof we have hereunto set our hands in presence of twowitnesses.

ALBERT EDWIN HGLBROOK. JOHN FRANCIS HARDING.

\Vitnesses:

F. G. MILLS, Ivon WILLIAMs.

